{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"submitter":["Suarez-Rodriguez T"],"funding":["Agencia Estatal de Investigación","Gobierno del Principado de Asturias"],"pagination":["13079-13084"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC8518403"],"repository":["biostudies-literature"],"omics_type":["Unknown"],"volume":["27(51)"],"pubmed_abstract":["Gold(I)-catalyzed formal [4+2] cycloaddition of O-aryl ynol ethers 1 and enol ethers 2 is described. This intermolecular reaction between two electron-rich unsaturated systems takes place, under mild conditions, in the presence of 5 mol% [IPrAu(CH<sub>3</sub> CN)]SbF<sub>6</sub> as catalyst giving chromene derivatives with good yields. The cycloaddition is completely regio- and stereoselective, as well as versatile for both reactives. Silyl enol ethers can also react in the same way and under the same reaction conditions with quantitative yields. A plausible mechanism through a selective addition of the enol ether to the alkyne gold activated complex followed by an intramolecular aromatic electrophilic substitution is proposed. Several experimental results support the presence of a cationic oxonium intermediate prior to the aromatic substitution. The reaction represents a new entry to the chromene core."],"journal":["Chemistry (Weinheim an der Bergstrasse, Germany)"],"pubmed_title":["Gold(I)-Catalyzed Intermolecular Formal [4+2] Cycloaddition of O-Aryl Ynol Ethers and Enol Ethers: Synthesis of Chromene Derivatives."],"pmcid":["PMC8518403"],"funding_grant_id":["CTQ2016-76840-R","PID2019-107469RB-I00/AEI/10.13039/501100011033","Predoctoral scholarship"],"pubmed_authors":["Suarez-Rodriguez T","Ballesteros A","Suarez-Sobrino AL"],"additional_accession":[]},"is_claimable":false,"name":"Gold(I)-Catalyzed Intermolecular Formal [4+2] Cycloaddition of O-Aryl Ynol Ethers and Enol Ethers: Synthesis of Chromene Derivatives.","description":"Gold(I)-catalyzed formal [4+2] cycloaddition of O-aryl ynol ethers 1 and enol ethers 2 is described. This intermolecular reaction between two electron-rich unsaturated systems takes place, under mild conditions, in the presence of 5 mol% [IPrAu(CH<sub>3</sub> CN)]SbF<sub>6</sub> as catalyst giving chromene derivatives with good yields. The cycloaddition is completely regio- and stereoselective, as well as versatile for both reactives. Silyl enol ethers can also react in the same way and under the same reaction conditions with quantitative yields. A plausible mechanism through a selective addition of the enol ether to the alkyne gold activated complex followed by an intramolecular aromatic electrophilic substitution is proposed. Several experimental results support the presence of a cationic oxonium intermediate prior to the aromatic substitution. The reaction represents a new entry to the chromene core.","dates":{"release":"2021-01-01T00:00:00Z","publication":"2021 Sep","modification":"2025-04-19T15:11:16.292Z","creation":"2025-04-19T15:11:16.292Z"},"accession":"S-EPMC8518403","cross_references":{"pubmed":["34278626"],"doi":["10.1002/chem.202102534"]}}